style: apply nightly rustfmt import grouping across the workspace

rustfmt.toml sets group_imports, imports_granularity and imports_layout,
which are nightly-only; agents formatted with stable rustfmt, which
ignored them. This is a formatting-only pass with `cargo +nightly fmt`.

Test Plan:
- cargo clippy --workspace --all-targets -- -D warnings
- cargo test --workspace

crates/ghostty-cli/src/edit_config.rs

@@ -1,12 +1,10 @@
 //! `+edit-config` (ZIG/src/cli/edit_config.zig).
 
-use std::io::Write;
-use std::os::unix::process::CommandExt;
+use std::{io::Write, os::unix::process::CommandExt};
 
 use ghostty_config::config::Config;
 
 use crate::error::Error;
-
 pub use crate::options::NoOptions as Options;
 
 /// The `edit-config` command opens the Ghostty configuration file in the